Pneumatic musical instrument



2' ,Sheets-Sheet 1.

(No ModeL) M. CLARK.

PNEUMATIC MUSICAL INSTRUMENT.

Patented Jan.' 26

(No ModeL) 2 Sheets-'Shet 2.'

lVL CLARK. PNEUMATIG'MUSIGAL INSTRUMENT.

N0. 576 032. l Patented Jaln. 26;.1897.

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CQ U /l Q M U 43 C' @lo L... E l? A30 UNITED STATES PATENT OFFICE.

MELVILLI CLARK, OF CHICAGO, ILLINOIS.

PN EU MATIC MUSICAL INSTRUMENT.

SPECIFICATION forming part of Letters Patent No. 576,032, dated January 26, 1897'.

Application filed July 27, 1896. Serial No. 600,654. (No model.)

To all whom, may concern.'

Be it known that I, MELVILLE CLARK, a citizen of the United States, residing at Chicago, count-y of Cook, and State of Illinois, have invented certain new and useful Improvements in Pneumatic Musical Instruments, which are fully set forth in the following specification, reference beinghad to the accompanying drawings, forming a part thereof.

rlhis invention relates to improvements in musical instruments in which the soundproducing devices are caused to speak by means of so-calied pneumatic motors;77 and it consists in improvements ina construction by which the pneumatic is made much more sensitive than heretofore-that is, adapted to respond to less suction or pressure in the wind-chest, and, specifically, adapted to respond to less suction or pressure than is necessary to cause the sound-producing devices themselves to speak. It is therefore peculiarly adapted to reed or pipe instruments in which the suction or pressure of air in the wind-chest, producing a current of air past or through the sound-prod nein g device, is the means of making the latter speak, the same suction or pressure being the means of operating the pneumatics. In such instruments it is very important that a minimum quantity of air should be used to operate the pneumatic devices, so that the work imposed upon the bellows in respect to the quantity of air which they shall pump sha-ll not be excessively increased by the employment of the pneumatics beyond what would be required for the sound-producin g devices themselves. This consideration has led to the employment of what maybe termed primary pneumatics-that is, pneumatics which are primarily operated by the suction or pressure in the wind-chest-to operate the valves which control the communication with the windchest of secondary pneumaties, such secondary pneumatics being the means of causing the sound-producing devices to speak. This permits the use of a very small primary pneumatic and of a secondary pneumatic of any necessary size to operate the sound-producing device, the quantity of air required to be pumped or drawn by the bellows being determined by the size of the primary pneumatie, independently of the size of the secondary or motor pneumatic. In such combinations of prima-ry and motor pneumatics which have been commonly employed the primary pneumatic has been generally located within the wind-chest, so that its area might be subject to the tension of air in the wind-chest. In organs or other musical instruments operating by exhaust action in the wind-chest, producing suction thereinto through all passages connnunicating with the interior of such wind-chest, this construction has been found to necessitate the employment of a spring whose function is to collapse thc primary pneumatic when the coinmunication of that pneumatic with the eX- terior air is closed by the controlling devices, such collapse being permitted by a very restricted vent-aperture with which the pneumatic is provided inside the wind-chest. Obviously the inflation of the pneumatic by exterior air, when the controlling devices admit such air, will be effected against the resistance of this spring, and the degree of rareiication necessary in the wind-chest in order to produce the action of a pneumatic must be such as to afford, by the dii-'ference between the tension of the air within the bellows and that of the external air, at least suiiicient force to overcome the spring, and since the collapse of the bellows effected by-the reaction of this spring must be practically instantaneous, in order that the response of the reeds to the action shall be prompt and that the tones shall not overlap each other, and since the collapse must be eii'ected by the discharge of the air through a very small vent-aperture in the primary pneumatic, the spring requires considerable power in order thus to drive the air out through the small orifice instantaneously. The result is that in practice the minimum degree of rareiication in the wind-chest which will cause the lightest reeds to speak is utterly insufficient to operate the pneumatics. For this reason the iiner modulations of intensity of tone of organs operated pne um aticallycannot be produced except by muifling devices in the nature of swells-that is, the tension in the wind-chest, being the least which is sufficient to operate the pneumatic devices, is suflicient to produce a very loud tone from the reeds, and softer tones are only producible by muiiiin g such loud tones. Such organs,

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therefore, as hitherto constructed are not eal pable oi line gradz'itions ol tone, which, iii an l organ operated from the keyboard and by t strictly mechanical con neetions from the'keys to the reed valves, are effected by the operator modifying; the action of the bellows to produce the expression desired Vfrom the reeds. 'llie advantage, therefore, of reducing the force necessary to operate the j iiieuiiiz'rtics to and below the degree ol. force necessary as a minimum to eause the reeds to speak is that thereby it becomes possible to modulate the intensity of the tone produced and so to vary the expression atthe will of the operator who controls the bellows, and thereby to vary it in every degree,and notmerely withsuchstelr 1Jy-step mmliiieatioiis as can be effected by means ol' swells. 'llie means which l employ for this result consist, primarily` in locating both the prin'iary and the motor pneumatics outside the wiml-eliest in such relation that springs in coiineiiftion with such pi'iei'iiiiatics may be dispensed with.

In the drawings, Figure l is a vertical foreaiid-aft section of a port-ion of the wind-chest and pneumatic action of an organ having' my iiiiprovemeiits. Fig. 2 is a similar section of like parts of an organ having duplex arrangex ment of niotor-piiieuiiiatics, reed -ehaiiibers, and valves eoi'jperating` with each primary pneumatic. Fig. l is a similar vertical foie and-aft section of a pneumatic action Vresembling that seen in Fig. 2, but having,` tliepi'imary pneumatic placed horizontally instead of vertically. inf.,r a iiiodilieation olI the primary pneumatic. Figs. 5,b,and aredetailseetions representing amoditication of the prin'iaivpneumatic in respect to itsv connections with the wind-chest, said ligures em'responding, resiiectively,to Figs. l, and Figs. tl and t) are inagnilied detail sections of the valves operated by the primary piieuniaties corresliiondinp)l Vlo two formsof suoli. valves shown7 respectively, in Figs. l, 2, and 5:3 and in Fles. 5, li, and 7.

A is the wind-chest. ln liig. ll have shown one reedsbloelithereon havingI two reed-eham bers controlled by a single valve i3. rl`liis valve is operated by motor-pneumalie C, mounted upon the Vfoiward vertical side ol the wind-chest and operating the reeitvalve by means of a bell-eranli, lever ("3 and suitable flexible connections from. its arms, respectively, to the pneumatic 'l and the reedvalve l5.

I do not limit myself in any respect to the specific situation oli' the iiiot ii'pneumatic or of the reed-valve.

D is the primary pneumatic. ln the form ward vertical side ot' the wind-chest and is in the form of a bellows whose movable side is suspended atits upper end and escillates between the fixed side and the forward side of the wind chest. The primary pneumatic communicates with the wind-chest through a duet d, which is restricted at its mouth-open Fig. t is adetail section showmoose ing into the wind-chest by a dish d', through which a very small yjninctiire is made. 'lhe primary pneumatic also coiiimiiniiatles with the outer air thi-(nigh a duet, trepreseiiled by the tube D'.) ylliis tube may extend to a trackeisranee where Vthe 'access of air will be Controlled by the traveling perforated sl rip iii a mannerwell ui'idersteod, and ilI inz'iybecontrolledinanyothernianneratwill,andinsomo ol.' the forms of inyiiivei'ition herein shown the primary pneumatic has double communica-` tion with the outer air, one commuiiicalioii beine' controlled by a perforated strip at a tracker-range and the other beine'controlled by a valve operated by a hey ot' the manual. The motor pneumatic eoininuiiiinites by means of the duct C, Ytermed in the `foi-ward wall oi' the wind-chest', both willi the interior oli' the'wiiitl-chestatel and with the exterior air at em. Valves ll and F, mounted en the same stem e, control Athese two openings, iespi -i tively, the valve l beine, formed on orseciired to the oscillaiiingsidc ofthe bellows which eonstitutes the primary pneumatic, so that' the movement of that side olf the ipiiieuina'lic in one direction or the other seats one valve or the other and puts the motor-pneumatie in cone inunieation eitl'ier with the interior of the wind-chest or with Vthe exterio alix tiaid os cillating wall et' the primarypneumal ic, pend-- ent, as described, hangt, Aiiorinnllynlhat is, when free from the influence of the windchest or any extraneous force-with llie valve F iii contact with its seat at the orifice el".

lt will be understood that when the air in the windafhest is i'aielied by the puini'iiiie' action of thebellows the primary ijiiieuniatir, being in communieatioii with the wiiid--i'liesl through the duet d, is virtually a continuation oli' the wind-chest and subject to the same rarelicatlon of its contents and is there Vfore collapsed, and its oseillatingrsde is held away from the side ot' the wiiid-chest, carrying,r the valve l" oft its seat and seating the valve lil, thus giving the moto@pnei'imatie communication willi the exterior aii'aiid iil tinger off its eommiinicalion with the wind chest'. lliis condition ol'affairscontinues so loiigas the communication of the Aprimary ljineiimatic with the exterior air through the duct d is closed, but when said duet is unn covered at its outer end, as by the registra tion ofan aperture of the ti'avelii'ig perforated paper strip with the mouth of the duet attlie tracter-range, atmospheric pressure beine' admitted freely to the pneumatic and llieexhaiist through the puiietureifl dish d lieinjwIl very restricted, the primary pneuiiialie las l.cornes inflated 'normally and the valve li shown in Fig'. l, it is also mounted en the fort comes to its seat, the valve 'it beine' opened, thus cutting oft.'eoiiiinuniealioii of the motorpneumatic with the outer air and estalilisliing' communication of the same wi th. the windchest and causing collapse of the ii'ioiior-pneumatie under exterior atmospheric pressure, the connections from the motor-pneumatie being such that the movement of its oseillat ICO ing wall involved in such collapse causes the sound-producing devices to speak, as in the case of a reed-organ, by lifting the reed-valve D. This condition continues so long as the mouth of the duct, which admits atmospheric air to the primary pneumatic, remains uncovered, but ceases, the parts returning to the original positions, whenever that duct is closed, since then the suction from the windchest collapses the primary pneumatic. In this construction it will be observed that all the'valves and both the pneumatics operate without springs, and, furthermore, that the oscillating parts of the pneumatics being pendulous the operation involves the minimum resistance, even by the weight of the moving parts.

In practice, the bellows-walls of the primary pneumatic, which must be practically air-tight, because these pneumatics are, as stated, practically a continuation of the windchest, have a slight elasticity, and this elasticity is taken advantage of to insure the normal seating of the valve F against the side of the wind-chest, since without care in this respect the slight stiffness and elasticity of material employed for this purpose might sometimes operate to hold the valve off its seat, even contrary to the action of gravity, by which it will be normally seated, but this precaution is only taken because it is not practicable to construct these small pneumatics so that invariably the bellows-walls at their normal condition shall tend to hold the valve F in the same position in which it is held by gravity-that is, just barely resting at the outer surface of the wall of the wind-chest. By thus dispensing with all devices exerting pressure to seat the valves or collapse the pneumatics I produce an instru inentin which the pneumaticswill act upon the very slightest suggestion of rareication in the windchest, and long before the rareiication has reached a degree sufficient to make the reeds speak. It thus becomes possible to moderate the intensity o'f the tone of the instrument precisely as if the reeds were being manipulated by hand or by strictly mechanical connections with the manual, the lightest tone of which the reeds are capable being producible when the reed-valves are operated by pneumatics, and all variations from the lightest to the most intense being effected by varying the operation of the bellows.

In Fig. 2 I have shown my invention applied in a reed-organ in which each primary pneumatic controls the action of two motorpneumatics, such motor-pneumatics operating the valves of independent sets of reeds, the motor-pneumatics being placed horizontally instead of vertically, and overhanging the reed-valves which they respectively operate, the construction in respect to the arrangement of the motor-pneumatics and the reed-valves being that which is shown in my application Serial No. 573,592, filed December 28, 1895. The reed -valves B B, operatin01 over reed-chambers which are mounted, respectively, upon the front and rear sides of the wind-chest A, are respectively operated by horizontal motor-pneumatics C C, placed heel to heel, overhangin g the reed-valves, respectively. These motor pneumatics are mounted upon the under side of a board A', upon the upper side of which is a supplement A2 of the wind-chest, which is supported above the wind-chest A proper by hollow standards, affording communication through portsl A80 from the wind-chest proper to said wind -chest supplement A2. The primary pneumatic D is mounted upon the forward side of the wind-chest supplement A2 in precisely the same manner as in Fig. l, the duct d, restricted by the perforated disk d', being the means of air communication from the wind-chest to the interior of the pneumatic, Dl being the duct leading to the tracker-range. The duct C,which leads from the interior of the m otor-pneumatics, extends from the cross-passage C10 up through the board A on the forward side of the windchest supplement A2 into the cross duct which at the port c opens into the windchest supplement and at the port 010 opens to the exterior air, said ports being closed by the valves E andF, respectively, operated, as in Fig, 1, by attachment to the oscillating side of a primary pneumatic D. It will be understood, therefore, that the operation is precisely the same in this structure as that shown in Fig. l.

In Fig. 3 l have shown the primary pneumatic placed horizontally instead of vertically and having its moving side overhan gin g the port 010, so that it operates more positively by gravity to seat the valve F than in the construction in which it is pendulous. l have shown this arrangement and position of the primary pneumatic in connection with the duplex construction and arrangement of motor-pneuinatics which is shown in Fig. 2. For the purpose of such an arrangement of the pneumatics the wind-chest supplement Ab is supported by the hollow standard A3 in such manner as to leave its under side, instead of its forward side, exposed for the purpose of mounting thereon the primary pneumatic D, and in this construction the iiXed wall of the primary pneumatic is mounted directly against the under wall of the wind-chest supplement and protru des beyond the wind-chest supplement at the rear to afford convenient means of connect-ing with the primary pneumatic the duct D', which leads from the tracker-range. The passage C', having the cross-passage C10 for the two motor-pneumatics, in this construction leads from the windchest proper, A, up through the board A, on the under side of which the motor-pneumaties are mounted. The valves E and F operated by the moving side, which is the under side, of the pneumatic control the ports c' andclo, as in the construction shown in the other figures.

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in all of these :forms provision maybe made for operating the instrument by a manual instead of by means of the perforated Sheet traveling over the tracker-range, and in all the formel this maybe done Vin either one of two ways-to wit, either by mechanif'al connectieus` from the keys of the manual to the reed-valves l, nn'lltingl a mechanical action entirely independent of the pneumatic action, Or by providing the primary pneumatic with a communication with `the exterior air, in addition to that which it obtaine through the pipe wh ich leads to the t raelier-range,an d controlling such additional communication by a valve operated by means of connection with a manual-key. rlhe latter means is illus'- tratied in the drawings. in the form shown in Fig. l the second air communication for the primary pneumatic is afforded by mea ne of the duet g Vin the board which forms t-he side of the wlmi-chest, such duct leadingr into the duct d. in the form Shown in Fig'. 2 the same function is performed by the duet g", formed in the board. G, mounted on the top of the board A and having; 'the fixed. side of the prin'iary pneumatic mounted against its rear edge, the duct g extending on `through the fixed wall and thus leading,r into the pneu matie-chamber. ln the form shown in Fig. 3 the Same Afu'nctitin is performed by the duct; gl, which is made in the board A, on which the primary pneumatic is Supported, said d uct continuingi 'u p through the blocli D, which forms the heel of the primary l'meumatic. ln each ease the outer end of the duct which thus affords the second outer air connection of a primary pneumatic is controlled by a valve `ll on a lever 1T, suitably fulcrumed at ite rear end upon any convenient fixed part and hav ing at its Vforward end Suitable means Yfor mechanical connection with a manual-liev, aS the link li?.

The Specilie means by which mechanical connection from the man ual-key, either to the valve ll or to the reed-valve l2, is made constitutes; no part of the present invent ion., and. I have therefore not illustrated any meansl for making' the connection with the valve l, Since many obvious modes and meansfor purposse will occur to Vthofse familiar with the art'.

in the principal iigures l have Shown the primary pneumatic as otthe bellow@ ferm; but Ido notlimit mycelf to this form. Other well-known forms of pneumatica may be entpleyed, such, :to r example, as the form shown in Fig. -l-, in which a diaphragm Yfrom behind or underwhich a duct leads te the wind-chest is substituted t'or the oeeillatini;` eide bellows. This form has one at'lvantage over a bellowe` form in that Vit is more easily made air-tught', as it is eesential the primary pneumatic should be when it is exterior to the windcheatln the diaphragm form et pneumatic the valve l", mounted on the diaphragm, will be held normallymthat is, by virtue of its Struct; u re and. the action of gravity upon it without 'the influence of the win d-cheSt-in contact with its Seat by the diaifihragm at its normal o.\:ition. The easiest action in obtaiiied by ma living," the ifliaphragm so that normally when tree l'rom the influence of the wind -eheal it; bulgey slightly outward, an eeen in lf`i5. fi, and doe not fluctuate t'ar ent'iugh to reverse the direction of ita curvature or fullneei7 but iaatopped bythe Seating of the valve lG before it han moved farem'nlgh to haye a ternlency to bultethe other way. This outwzn'd-lnilging tendency of the diaphragm thurs .inn-malty seat` the valve with the Same n"t'ect'ae` inthe penduloufs form. rl`he valve ia treated by graritv withoutfecneible preemn'e upon its; seat. '.tlnl Same result as to normal rseating'of the valve by the diaphragm atitbnormal position would be attained it.' the diaphragm were normallyA straight and aui'ticiently elafstie to he dopressed by the Suction experieneeit from the wind-cheat; but thisl would relpiire tensile` elasticity, and the diaphragm :lo eonatruetwl cannotbe made so delira telynensil ive to el igrh t raretcation in the wim'tcheist au a diaphragm applied with a little ilullnea, causingl it to bulge toward the v; -lveeeat By the term primary pneumatic ith' [Illif ployed in the above epeeitication and in my tion in a train which (.oinprimisv a :unondary pneumatic or lmeumatiea nlnnse ultimate aetion causen the sound--prodneine' device-i to speak. This term thun need therefore e\; cludes pnetnnalieis which meehaniimlly operate Vthe moana` for canaille' the ain1ml.p|o lin ing' devices` to apealc and which are included in the term motor-pnclimatica" ae uned. in thi` Specification. The imptn'tauee ot' these dietinctionfi will be umleretoedA when. it is re membered that in conatrui-.tieneI in which a pneumatic is canned or permitted to operate in amusical inetruincnt for any nu'poee by admitting` atmospheric pressure to il', un in all coimtructionei in which a perforated sheet or equivalentY device in the menne' employtnh there is unavoidably a constant wante ol.' air while the pneunmtie ifs liept time expoiied to the atmoapherie prenaitrem-tha t in to nay, while 'the Soundproducing device in. beine caused to Speak. The pneumatic which operates the e umlined ueinjj|` device, :ui by operatingI Athe reed-valve in the ease ol.' a reed-- organ, termed the inetor-pneumatie, must have fiul'licient area to afford the .necessary power to operz'ite the Vvalve er eipiivalent de vice, and if auch motta-pneumalie in alno Ille primary j nnnnnatie (wlnnse action irs eausetl b` fadmittinnatmen iheric resaure lo it in or-A der that Such pneumatic should actr pronulilly both in opening and chieing the reed-valve or perfor-innig' whatever function dependa upon ite action for commencing and terminiuirr;r the speaking of the Sound-producine dern-o the Vent or oriiice through which the air is w fated or drawn Yin lin the action ot' the pneumatic, which continues While the exterior air communication is open, must be proportioned properly to the size of the pneumatic and must therefore be larger in proportion as the pneumatic is larger. lf the primary pneumatic therefore be made to serve also as the motor-pn eumatic,the waste of air will be very great, and the duty thus imposed upon the bellows is liable to become excessive, necessitating either very large or very rapidly-acting pumping devices. These considerations have led to thc almost universal practice of interposing between the pneumatic which is operated by a perforated strip or other means for admitting external air through such pneumatic and the means for immediately operating the sound-producing devices a secondary pneumatic, whose action, either inflation or collapse, shall be caused by changing its communication from the external air to the wind-chest, or vice versa, so that each action (inflation and collapse) shall consume only the quantity of air which the pneumatic rcquircs for inflation or expcls in collapse.

My present invention has to do strictly with structures in which there is a primary pneumatic in the sense above defined and a secondary pneumatic in the sense above indicated, since only when both are employed for the purpose for which the employment of both is useful does the occasion arise for discriminating between the interior and exterior location of such pneumatics with respect to the wind-chest.

ln Figs. 5, 6, and 7 I have shown a modification of the primary pneumatic in respect to the connection thereof with the wind-chest, the modiiication being designed for the purpose, primarily, of accomplishing, in respect to the initial seating of the valve F, the same thing that is accomplished by the mounting of the pneumatic so that by the action of gravity alone said valve normally reaches its seat. The same thing also is accomplished by the construction of the pneumatic shown in Fig. t, in which the bulging of the diaphragm tends to hold the valve normally at its seat. In the form shown in these figures there is one passage leading through the wall of the wind-chest in place of two passages shown in the principal figures.

In place of the duct d shown in the principal ligures I employ, in the form shown in Figs. 5, 6, and 7, a duct drb through the stem of the valves E and F, said stem indicated by the letter e, being thereby rendered tubular. The disk CZ' is then applied over the inner side of the valve E, through which the duct in the stem e opens, as in the other construction it is applied over the inner end of the duct d. This change in structure of the primary-pneum atie connection, when applied to the form shown in Fig. 3, dispenses entirely with the supplemental chamber Al and the standards A3, leading thereto. The action of the modified device is that when the communication of the primary pneumatic with the outer air is opened, admitting atmospheric pressure Within the pneumatic and causing it to be drawn in through the pneumatic into the Wind-chest through the puncture in the disk d', the in-rush of air through the tubular stem ea and against the under side of the punctured disk d tends to pull the valve-stem inward to unseat the valve E and seat the valve F, precisely as in the form shown in Fig. l, for example, and the pendulous position of the moving side of the pneumatic under the action of gravity tends to cause the valve F to move toward its seat as the moving side of the pneumatic swings pendulous-like when released from the suction which holds the pneumatic collapsed. In all the forms shown the valve E, being exposed to atmospheric pressure at the outer side and to diminished pressure at the inner side, tends to move inward as soon as the force exerted upon it by the primary pneumatic ceases by the admission of atmospheric air into the latter.

In the form shown in Figs. 5, 0, and 7 an additional influence of the same nature operates through the tubular stem en upon so much of the area of the disk d' as covers the duct in the stem (Za-that is, the area equal to that of the duct less that ofv the puncture in the disk d. This influence, tending to move the valves in the same manner as they tend to move by gravity, is independent of the influence first above mentioned, due to the frictional action of the air as it moves inward through the duct in the stem dil.

Since the primary pneumatics are constantly, during the operation of the instrument, exposed to suction, being in communication interiorly with the wind-chest and being cxteriorly exposed to atmospheric pressure, some waste is liable to occur through the tissues or diaphragms of such pneumatics, and the employment of the tubular stem for the 'valves E and F, as illustrated in Figs. 5, 6, and 7, affords an opportunity to reduce this possibility of waste at least one-half by providing within the primary pneumatic a cushion or seat d2, secured to the inner wall of the fixed side of the pneumatic on which the inner end of the tubular stem d shall seat when the pneumatic is collapsed, thus closing the communication between the interior of the pneumatic and the wind-chest after the partial vacuum necessary to cause the collapse of the pneumatic has been produced therein. This partialvacuum will be gradually diminished by the leakage until the pressure of the end of the tube upon the seat relaxes sufficiently to permit the air to be drawn past the seat into the wind-chest by the suction operating from the latter, thus restoring the vacuum again, but never permitting sufficient movement of the valves E and F to operate to reverse the connection of the 1n eter-pneumatic and cause it to operate. The loss by leakage is diminished by this means, because the partial vacuum in the IDD pneumatic which causes such leakage is a stetiulily-diminishing Atorce until it hecomes so far diminished as lo permit 'its resteration inthe manner described. Such restoration occurs instantly when the pressure on the cushion permits the air to pass, so that the average .'acuum .is therel'ore about` onehalf the maximuni, and the aggregate lealiagee is therefore reduced ahoutI ene-hall'.

Since the motion ol the stem et the valves ll and l? when attached to an oscillating or hinged bellows side is not directlylongitudinal with respect to the stem, the two Valves require to have their seating-surfaces not exactly parallel, in order that they may each in turn seat properly at the ports which they respectively control. 'lo avoid the `necessity ol` the very accurate :uljustment which will he necessary to insure perfect seating in view ot' this feature, l prefer vte make the valve E loose en its stem, so that it may adj ust itself to its seat when it strikes it. This feature cannot he recognized hy the eye in the actual construction nor in drawings et actual size, hut l have shown in Figs. t) and lt) magnilied details `from which ity may he understood. Vhcn the solid stein sueh as shown in lilies. ll, 2, and 3 is employed, such stem extends loosely through the Valve l2 and is provided with a head e to stop the valve and adapted te pull it onto its seat at whatever slight an- `ele thereto it may strike it. ln the tuhnlar tforin shown in Figs. tl, T, and the tubular stem is flanged at the end l'or the saine purpose and with the same et't'eet, the disk d" heing made 'tast to the outer surt'aee ot' the llange reln'esented hy it, ln all the 'forms the necessary adjustments et the valves lil and lf to each other in respect te their distance apart may he made hy screwing their stem more or less through the valve l?, and, it' necessary, into or through the side et the hcllows to which the Valve li is attached.

l claimml. ln a pneumatic organ, in combination with an exhaust wind-chest, a primary pneumatic and a ineter-pneuniatic hoth exterior to the wind'chest and com munieating therewith tor exhausting and with the outer air tor'vent- I ingl said pneumaties; the valves which control the exhaust and vent ports el' the motorpncumatic being,` connected. to and operated hy the primarypneumatic te exhaust the motor-pneumatic when the primary pneumatic Vis rented, and te rent said niotonpneumatic when the primarypneumatic is exhausted; connections from the meter-pneumatie hy which the seunil-predueing,` dericcs are caused te speak when said motor-Inieumatie cellapsed, and. suitable means :t'or uncovering the vent et' the primary pneumatic; the rent` valve ofthe metoipneumatic heing at its scat normally under the influence of gravity when free from any inlluence preceeding from the wind-chest.

2. In a pneumatic Orga-n, in combination wit-h an exhaust wind-chest, a primary pneumatie and a motois-pneumatic hoth exteriorI to the wind-chest and communieating therewith tor exhausting and with theouterair torrentine` said pneumatiies; the valves which eeutrol the exhaust and vent ports ol' the motorpneumatic heing conneetetfl to and operated hy the primary pneumatic t o exhaust the motor-pneuimitie when the primary meumatic vented, and to 'vent said inetor-pneumatie when the primary pneunnitic is exhausted; coiiucetitnis t'rom the lnoter-piieumatic hy whichthesounftproducingdevicesarerausial to speak when said motor-pneuntatie is (rollapsed, and suitahle means tor uneoveriner the vent ol the primary pneumatic; the yentvalve et the motor-pneumatie and its connection te the primary pneumatic hein; exterior te Vthe wind-chest, said primary pnenmathi heini; adapted normally under the intluenee of gravity and when tree `l'rom any intluenre preceeding' Yl'roin the wind-chest to stand ex panded and in position to hold said ralve at its seat.

i3. ln a pneumatic organ, in comhination with an exhaust wind-chest, aprimurypneu matic and a metorpneumatic hoth exterior to the winttchest and comm unieating therewith for exhausting and with theouter ai r l'or 'ventingI said pneumaticili; the valves which control the exhaust and vent ports el the motor-- pneumatic being connected to and mierateii. hy the primary pneumatic te exhaust the motor-pneumatic when the primary rmeumatitI is rented, and to vent said motCuf-pneumatie when the primary pneumatic 's exlmusted; connections itrom the motor pneumatic hy whiehthesound-produeing'rflevicesarecaused to speak when said 1netor-pneuniatie is eol lapsed, and suitable means t'or uncovering the yent et the primary pneunn'itie; said primary pneumatic heingl adapted normally when vented and thereby relieved li'rom the intlu* ence et the winttehest, to expand hy the are tien of gravity on its moving wall to the extent necessary to hold the exl1aust\alre ot.' the motor-lmeumatie et, ts seat and the venivalve el said pneumatic at its seat'.

t. ln apneumatic organ, .in eeinhinatiou with an exhaust;windsehest, a primarypneumatic and a motor-pneumatie hoth exterior to the wind-chest and. communieatinfej,y thcrewit h for exhausting;` and with the ou ter airtorvtm t 'ing raid limeumatics; the valves which eontrol. the exhaust and rent ports ol the motorpneuinatie heine` connected. lto and operated. hy the primary pneumatic to exhaust the 1no tor-pneumatic when the primary pneumatic is vented, and to vent said 'metor-pnenmatie when. the prinuiry pneumatic is exhausted: connections from the nietoepneu'matie hy which the souml-preduci ne derices are ea used, to speak when said motor-pneumatic .is eollapsed, and suitable means l'or unemering the vent et the primary pueumz'itie; the exhaust cennnunication of the primary pneumatic with the wind-chest heini; restricted .relan 'tively to the yent el' said prinnrry pneumatic,

and the vent-valve of the motor-pneumatic being adapted normally, under the influence of gravity, when the primary pneumatic is vented, to stand at its seat.

5. In a pneumatic organ, in combination with an exhaust wind-chest,a primary pneumatic and a motor-pneumatic both exterior to the wind-chest and communicating therewith for exhausting and with the outer air for venting said pneumatics; the valves which control the exhaust and vent ports of the motor-pneumatic being connected to and operated by the primary pneumatic to exhaust the motor-pneumatic when the primary pneumatic is vented, and to vent said motor-pneumatic when the primary pneumatic is exhausted; connections from the motor-pneumatic by which the sound-producing devices are caused to speak when said motor-pneumatic is collapsed, and suitable means for uncovering the vent of the primary pneumatic the moving wall of the primary pneumatic being pendulous and at normal position under the iniiuence of gravityvhen said pneumatic is vented and freed from the in- Iluence of the wind-chest, adapted to hold the motor-pneumatic vent-valve at its seat.

G. In combination with the wind-chest, a primary pneumatic and a motor-pneumatic whose communication with the wind-chest is controlled by the primary pneumatic; the valve which effects such control having its stem tubular and constituting a communicating duct between the wind-chest and the primary pneumatic.

7. In combination with the wind-chest, a primary pneumatic and a motor-pneumatic having its communication with the external air controlled bythe primary pneumatic, the valve which effects such control having its stem tubular and constituting the communieating passage between the wind-chest and the primary pneumatic.

8. In combination with the wind-chest, the primarypneumatic exterior thereto and a motor-pneumatic whose communication is controlled by the primary pneumatic; the valve which effects such control having a stem tubular and constituting a communicating duct between the wind-chest and the primary pneumatic.

9. In combination with the wind-chest, a primary pneumatic exterior thereto; a motorpneumatic also exterior thereto; valves which control the communication of the motor-pneumatic with the wind-chest and with the external air heilig operated by the primary pneumatic and being mounted on a common stem, said stem being tubular and constituting the communication between the windchest and the primary pneumatic.

IO. In combination with the wind-chest, and an exterior primary pneumatic, a tube which is attached to the iiuctuating wall of the pneumatic and which extends into the windchest and constitutes the means of communication between the wind-chest and the pneumatic; and a pallet or valve within the pneumatic adapted to be seated over the inner port of said tube when the pneumatic is collapsed.

ll. In combination with the wind-chest, a primarypneumatic exterior thereto and a motor-pneumatic whose communication with the wind-chest and with the outer air is controlled by the primary pneumatic; the valve which effects such control having its stem tubular and constituting the communicating duct between the wind-chest and the pneumatic; and a pallet or seat within the primary pneumatic on which the inner port of said duct seats when the pneumatic is collapsed.

In testimony whereof I have hereunto set my hand, in the presence of two witnesses, at Chicago, Illinois, this 24th day of July, 1896.

MELVILLE CLARK. lVitnesses:

CHAs. S. BURTON, JEAN ELLIOTT. 

